I've run the Dyna III on my /7 for maybe 23 years. It replaces the points plate and eliminates the condensor, so if you want to change back on the road, you'll need to carry these along. It reuses the mechanical centrifugal advance...some people don't like that aspect. There are two separate pickups that can be used to differentially time the firing of each cylinder. A little fiddlely, but once set, it's set...no messing around.

I don't know much about the Boyer (there are several versions), but it has built-in advance curves, meaning the centrifugal advance is eliminated. I don't think you have the ability to independently time the cylinders.

I've had one of the pickups on my Dyna fail after about 15 years, so I'm on my second one. It may have been issues with grounding of the sensor plate...not sure.

I have Dyna III's on both a R75/5 and a R90/6. The one on my R90/6 has been there for over 10 years. I have had no problems. It makes the bike very easy to start. I wouldn't hesitate to recommend the Dyna III to anyone. I have no experience with the Boyer.